I switched from Arch to NixOS and I know many others who did too. For users inclined to use a distro such as Arch, NixOS feels like the natural next step.
I’ve had to do very, very little to my Artix desktop since setting it up that I don’t think I’ll ever switch unless my life constraints changed significantly. NixOS seems like a lot to learn. I’m happy to be proven otherwise and know I’m not alone in becoming very complacent to my setup once getting to Arch.
In recent years, NixOS has probably taken some of their enthusiast base too